1 /* 2 * Copyright (c) 2005 Jeffrey M. Hsu. All rights reserved. 3 * Copyright (c) 1982, 1986, 1988, 1990, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the University of 17 * California, Berkeley and its contributors. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93 35 * $FreeBSD: src/sys/kern/uipc_socket2.c,v 1.55.2.17 2002/08/31 19:04:55 dwmalone Exp $ 36 * $DragonFly: src/sys/kern/uipc_socket2.c,v 1.33 2008/09/02 16:17:52 dillon Exp $ 37 */ 38 39 #include "opt_param.h" 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/domain.h> 43 #include <sys/file.h> /* for maxfiles */ 44 #include <sys/kernel.h> 45 #include <sys/proc.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/protosw.h> 49 #include <sys/resourcevar.h> 50 #include <sys/stat.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/socketops.h> 54 #include <sys/signalvar.h> 55 #include <sys/sysctl.h> 56 #include <sys/event.h> 57 58 #include <sys/thread2.h> 59 #include <sys/msgport2.h> 60 #include <sys/socketvar2.h> 61 62 int maxsockets; 63 64 /* 65 * Primitive routines for operating on sockets and socket buffers 66 */ 67 68 u_long sb_max = SB_MAX; 69 u_long sb_max_adj = 70 SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */ 71 72 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 73 74 /************************************************************************ 75 * signalsockbuf procedures * 76 ************************************************************************/ 77 78 /* 79 * Wait for data to arrive at/drain from a socket buffer. 80 * 81 * NOTE: Caller must generally hold the ssb_lock (client side lock) since 82 * WAIT/WAKEUP only works for one client at a time. 83 * 84 * NOTE: Caller always retries whatever operation it was waiting on. 85 */ 86 int 87 ssb_wait(struct signalsockbuf *ssb) 88 { 89 uint32_t flags; 90 int pflags; 91 int error; 92 93 pflags = (ssb->ssb_flags & SSB_NOINTR) ? 0 : PCATCH; 94 95 for (;;) { 96 flags = ssb->ssb_flags; 97 cpu_ccfence(); 98 99 /* 100 * WAKEUP and WAIT interlock eachother. We can catch the 101 * race by checking to see if WAKEUP has already been set, 102 * and only setting WAIT if WAKEUP is clear. 103 */ 104 if (flags & SSB_WAKEUP) { 105 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 106 flags & ~SSB_WAKEUP)) { 107 error = 0; 108 break; 109 } 110 continue; 111 } 112 113 /* 114 * Only set WAIT if WAKEUP is clear. 115 */ 116 tsleep_interlock(&ssb->ssb_cc, pflags); 117 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 118 flags | SSB_WAIT)) { 119 error = tsleep(&ssb->ssb_cc, pflags | PINTERLOCKED, 120 "sbwait", ssb->ssb_timeo); 121 break; 122 } 123 } 124 return (error); 125 } 126 127 /* 128 * Lock a sockbuf already known to be locked; 129 * return any error returned from sleep (EINTR). 130 */ 131 int 132 _ssb_lock(struct signalsockbuf *ssb) 133 { 134 uint32_t flags; 135 int pflags; 136 int error; 137 138 pflags = (ssb->ssb_flags & SSB_NOINTR) ? 0 : PCATCH; 139 140 for (;;) { 141 flags = ssb->ssb_flags; 142 cpu_ccfence(); 143 if (flags & SSB_LOCK) { 144 tsleep_interlock(&ssb->ssb_flags, pflags); 145 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 146 flags | SSB_WANT)) { 147 error = tsleep(&ssb->ssb_flags, 148 pflags | PINTERLOCKED, 149 "sblock", 0); 150 if (error) 151 break; 152 } 153 } else { 154 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 155 flags | SSB_LOCK)) { 156 lwkt_gettoken(&ssb->ssb_token); 157 error = 0; 158 break; 159 } 160 } 161 } 162 return (error); 163 } 164 165 /* 166 * This does the same for sockbufs. Note that the xsockbuf structure, 167 * since it is always embedded in a socket, does not include a self 168 * pointer nor a length. We make this entry point public in case 169 * some other mechanism needs it. 170 */ 171 void 172 ssbtoxsockbuf(struct signalsockbuf *ssb, struct xsockbuf *xsb) 173 { 174 xsb->sb_cc = ssb->ssb_cc; 175 xsb->sb_hiwat = ssb->ssb_hiwat; 176 xsb->sb_mbcnt = ssb->ssb_mbcnt; 177 xsb->sb_mbmax = ssb->ssb_mbmax; 178 xsb->sb_lowat = ssb->ssb_lowat; 179 xsb->sb_flags = ssb->ssb_flags; 180 xsb->sb_timeo = ssb->ssb_timeo; 181 } 182 183 184 /************************************************************************ 185 * Procedures which manipulate socket state flags, wakeups, etc. * 186 ************************************************************************ 187 * 188 * Normal sequence from the active (originating) side is that 189 * soisconnecting() is called during processing of connect() call, resulting 190 * in an eventual call to soisconnected() if/when the connection is 191 * established. When the connection is torn down soisdisconnecting() is 192 * called during processing of disconnect() call, and soisdisconnected() is 193 * called when the connection to the peer is totally severed. 194 * 195 * The semantics of these routines are such that connectionless protocols 196 * can call soisconnected() and soisdisconnected() only, bypassing the 197 * in-progress calls when setting up a ``connection'' takes no time. 198 * 199 * From the passive side, a socket is created with two queues of sockets: 200 * so_incomp for connections in progress and so_comp for connections 201 * already made and awaiting user acceptance. As a protocol is preparing 202 * incoming connections, it creates a socket structure queued on so_incomp 203 * by calling sonewconn(). When the connection is established, 204 * soisconnected() is called, and transfers the socket structure to so_comp, 205 * making it available to accept(). 206 * 207 * If a socket is closed with sockets on either so_incomp or so_comp, these 208 * sockets are dropped. 209 * 210 * If higher level protocols are implemented in the kernel, the wakeups 211 * done here will sometimes cause software-interrupt process scheduling. 212 */ 213 214 void 215 soisconnecting(struct socket *so) 216 { 217 soclrstate(so, SS_ISCONNECTED | SS_ISDISCONNECTING); 218 sosetstate(so, SS_ISCONNECTING); 219 } 220 221 void 222 soisconnected(struct socket *so) 223 { 224 struct socket *head; 225 226 while ((head = so->so_head) != NULL) { 227 lwkt_getpooltoken(head); 228 if (so->so_head == head) 229 break; 230 lwkt_relpooltoken(head); 231 } 232 233 soclrstate(so, SS_ISCONNECTING | SS_ISDISCONNECTING | SS_ISCONFIRMING); 234 sosetstate(so, SS_ISCONNECTED); 235 if (head && (so->so_state & SS_INCOMP)) { 236 if ((so->so_options & SO_ACCEPTFILTER) != 0) { 237 so->so_upcall = head->so_accf->so_accept_filter->accf_callback; 238 so->so_upcallarg = head->so_accf->so_accept_filter_arg; 239 atomic_set_int(&so->so_rcv.ssb_flags, SSB_UPCALL); 240 so->so_options &= ~SO_ACCEPTFILTER; 241 so->so_upcall(so, so->so_upcallarg, 0); 242 lwkt_relpooltoken(head); 243 return; 244 } 245 246 /* 247 * Listen socket are not per-cpu. 248 */ 249 TAILQ_REMOVE(&head->so_incomp, so, so_list); 250 head->so_incqlen--; 251 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 252 head->so_qlen++; 253 sosetstate(so, SS_COMP); 254 soclrstate(so, SS_INCOMP); 255 256 /* 257 * XXX head may be on a different protocol thread. 258 * sorwakeup()->sowakeup() is hacked atm. 259 */ 260 sorwakeup(head); 261 wakeup_one(&head->so_timeo); 262 } else { 263 wakeup(&so->so_timeo); 264 sorwakeup(so); 265 sowwakeup(so); 266 } 267 if (head) 268 lwkt_relpooltoken(head); 269 } 270 271 void 272 soisdisconnecting(struct socket *so) 273 { 274 soclrstate(so, SS_ISCONNECTING); 275 sosetstate(so, SS_ISDISCONNECTING | SS_CANTRCVMORE | SS_CANTSENDMORE); 276 wakeup((caddr_t)&so->so_timeo); 277 sowwakeup(so); 278 sorwakeup(so); 279 } 280 281 void 282 soisdisconnected(struct socket *so) 283 { 284 soclrstate(so, SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING); 285 sosetstate(so, SS_CANTRCVMORE | SS_CANTSENDMORE | SS_ISDISCONNECTED); 286 wakeup((caddr_t)&so->so_timeo); 287 sbdrop(&so->so_snd.sb, so->so_snd.ssb_cc); 288 sowwakeup(so); 289 sorwakeup(so); 290 } 291 292 void 293 soisreconnecting(struct socket *so) 294 { 295 soclrstate(so, SS_ISDISCONNECTING | SS_ISDISCONNECTED | 296 SS_CANTRCVMORE | SS_CANTSENDMORE); 297 sosetstate(so, SS_ISCONNECTING); 298 } 299 300 void 301 soisreconnected(struct socket *so) 302 { 303 soclrstate(so, SS_ISDISCONNECTED | SS_CANTRCVMORE | SS_CANTSENDMORE); 304 soisconnected(so); 305 } 306 307 /* 308 * Set or change the message port a socket receives commands on. 309 * 310 * XXX 311 */ 312 void 313 sosetport(struct socket *so, lwkt_port_t port) 314 { 315 so->so_port = port; 316 } 317 318 /* 319 * When an attempt at a new connection is noted on a socket 320 * which accepts connections, sonewconn is called. If the 321 * connection is possible (subject to space constraints, etc.) 322 * then we allocate a new structure, propoerly linked into the 323 * data structure of the original socket, and return this. 324 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 325 * 326 * The new socket is returned with one ref and so_pcb assigned. 327 * The reference is implied by so_pcb. 328 */ 329 struct socket * 330 sonewconn_faddr(struct socket *head, int connstatus, 331 const struct sockaddr *faddr) 332 { 333 struct socket *so; 334 struct socket *sp; 335 struct pru_attach_info ai; 336 337 if (head->so_qlen > 3 * head->so_qlimit / 2) 338 return (NULL); 339 so = soalloc(1); 340 if (so == NULL) 341 return (NULL); 342 343 /* 344 * Set the port prior to attaching the inpcb to the current 345 * cpu's protocol thread (which should be the current thread 346 * but might not be in all cases). This serializes any pcb ops 347 * which occur to our cpu allowing us to complete the attachment 348 * without racing anything. 349 */ 350 sosetport(so, cpu_portfn(mycpu->gd_cpuid)); 351 if ((head->so_options & SO_ACCEPTFILTER) != 0) 352 connstatus = 0; 353 so->so_head = head; 354 so->so_type = head->so_type; 355 so->so_options = head->so_options &~ SO_ACCEPTCONN; 356 so->so_linger = head->so_linger; 357 358 /* 359 * NOTE: Clearing NOFDREF implies referencing the so with 360 * soreference(). 361 */ 362 so->so_state = head->so_state | SS_NOFDREF | SS_ASSERTINPROG; 363 so->so_proto = head->so_proto; 364 so->so_cred = crhold(head->so_cred); 365 ai.sb_rlimit = NULL; 366 ai.p_ucred = NULL; 367 ai.fd_rdir = NULL; /* jail code cruft XXX JH */ 368 369 /* 370 * Reserve space and call pru_attach. We can direct-call the 371 * function since we're already in the protocol thread. 372 */ 373 if (soreserve(so, head->so_snd.ssb_hiwat, 374 head->so_rcv.ssb_hiwat, NULL) || 375 so_pru_attach_direct(so, 0, &ai)) { 376 so->so_head = NULL; 377 soclrstate(so, SS_ASSERTINPROG); 378 sofree(so); /* remove implied pcb ref */ 379 return (NULL); 380 } 381 KKASSERT(so->so_refs == 2); /* attach + our base ref */ 382 sofree(so); 383 KKASSERT(so->so_port != NULL); 384 so->so_rcv.ssb_lowat = head->so_rcv.ssb_lowat; 385 so->so_snd.ssb_lowat = head->so_snd.ssb_lowat; 386 so->so_rcv.ssb_timeo = head->so_rcv.ssb_timeo; 387 so->so_snd.ssb_timeo = head->so_snd.ssb_timeo; 388 389 if (head->so_rcv.ssb_flags & SSB_AUTOLOWAT) 390 so->so_rcv.ssb_flags |= SSB_AUTOLOWAT; 391 else 392 so->so_rcv.ssb_flags &= ~SSB_AUTOLOWAT; 393 394 if (head->so_snd.ssb_flags & SSB_AUTOLOWAT) 395 so->so_snd.ssb_flags |= SSB_AUTOLOWAT; 396 else 397 so->so_snd.ssb_flags &= ~SSB_AUTOLOWAT; 398 399 if (head->so_rcv.ssb_flags & SSB_AUTOSIZE) 400 so->so_rcv.ssb_flags |= SSB_AUTOSIZE; 401 else 402 so->so_rcv.ssb_flags &= ~SSB_AUTOSIZE; 403 404 if (head->so_snd.ssb_flags & SSB_AUTOSIZE) 405 so->so_snd.ssb_flags |= SSB_AUTOSIZE; 406 else 407 so->so_snd.ssb_flags &= ~SSB_AUTOSIZE; 408 409 /* 410 * Save the faddr, if the information is provided and 411 * the protocol can perform the saving opertation. 412 */ 413 if (faddr != NULL && so->so_proto->pr_usrreqs->pru_savefaddr != NULL) 414 so->so_proto->pr_usrreqs->pru_savefaddr(so, faddr); 415 416 lwkt_getpooltoken(head); 417 if (connstatus) { 418 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 419 sosetstate(so, SS_COMP); 420 head->so_qlen++; 421 } else { 422 if (head->so_incqlen > head->so_qlimit) { 423 sp = TAILQ_FIRST(&head->so_incomp); 424 TAILQ_REMOVE(&head->so_incomp, sp, so_list); 425 head->so_incqlen--; 426 soclrstate(sp, SS_INCOMP); 427 sp->so_head = NULL; 428 soaborta(sp); 429 } 430 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 431 sosetstate(so, SS_INCOMP); 432 head->so_incqlen++; 433 } 434 lwkt_relpooltoken(head); 435 if (connstatus) { 436 /* 437 * XXX head may be on a different protocol thread. 438 * sorwakeup()->sowakeup() is hacked atm. 439 */ 440 sorwakeup(head); 441 wakeup((caddr_t)&head->so_timeo); 442 sosetstate(so, connstatus); 443 } 444 soclrstate(so, SS_ASSERTINPROG); 445 return (so); 446 } 447 448 struct socket * 449 sonewconn(struct socket *head, int connstatus) 450 { 451 return sonewconn_faddr(head, connstatus, NULL); 452 } 453 454 /* 455 * Socantsendmore indicates that no more data will be sent on the 456 * socket; it would normally be applied to a socket when the user 457 * informs the system that no more data is to be sent, by the protocol 458 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 459 * will be received, and will normally be applied to the socket by a 460 * protocol when it detects that the peer will send no more data. 461 * Data queued for reading in the socket may yet be read. 462 */ 463 void 464 socantsendmore(struct socket *so) 465 { 466 sosetstate(so, SS_CANTSENDMORE); 467 sowwakeup(so); 468 } 469 470 void 471 socantrcvmore(struct socket *so) 472 { 473 sosetstate(so, SS_CANTRCVMORE); 474 sorwakeup(so); 475 } 476 477 /* 478 * Wakeup processes waiting on a socket buffer. Do asynchronous notification 479 * via SIGIO if the socket has the SS_ASYNC flag set. 480 * 481 * For users waiting on send/recv try to avoid unnecessary context switch 482 * thrashing. Particularly for senders of large buffers (needs to be 483 * extended to sel and aio? XXX) 484 * 485 * WARNING! Can be called on a foreign socket from the wrong protocol 486 * thread. aka is called on the 'head' listen socket when 487 * a new connection comes in. 488 */ 489 void 490 sowakeup(struct socket *so, struct signalsockbuf *ssb) 491 { 492 struct kqinfo *kqinfo = &ssb->ssb_kq; 493 uint32_t flags; 494 495 /* 496 * Check conditions, set the WAKEUP flag, and clear and signal if 497 * the WAIT flag is found to be set. This interlocks against the 498 * client side. 499 */ 500 for (;;) { 501 flags = ssb->ssb_flags; 502 cpu_ccfence(); 503 504 if ((ssb == &so->so_snd && ssb_space(ssb) >= ssb->ssb_lowat) || 505 (ssb == &so->so_rcv && ssb->ssb_cc >= ssb->ssb_lowat) || 506 (ssb == &so->so_snd && (so->so_state & SS_CANTSENDMORE)) || 507 (ssb == &so->so_rcv && (so->so_state & SS_CANTRCVMORE)) 508 ) { 509 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 510 (flags | SSB_WAKEUP) & ~SSB_WAIT)) { 511 if (flags & SSB_WAIT) 512 wakeup(&ssb->ssb_cc); 513 break; 514 } 515 } else { 516 break; 517 } 518 } 519 520 /* 521 * Misc other events 522 */ 523 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 524 pgsigio(so->so_sigio, SIGIO, 0); 525 if (ssb->ssb_flags & SSB_UPCALL) 526 (*so->so_upcall)(so, so->so_upcallarg, MB_DONTWAIT); 527 KNOTE(&kqinfo->ki_note, 0); 528 529 /* 530 * This is a bit of a hack. Multiple threads can wind up scanning 531 * ki_mlist concurrently due to the fact that this function can be 532 * called on a foreign socket, so we can't afford to block here. 533 * 534 * We need the pool token for (so) (likely the listne socket if 535 * SSB_MEVENT is set) because the predicate function may have 536 * to access the accept queue. 537 */ 538 if (ssb->ssb_flags & SSB_MEVENT) { 539 struct netmsg_so_notify *msg, *nmsg; 540 541 lwkt_getpooltoken(so); 542 TAILQ_FOREACH_MUTABLE(msg, &kqinfo->ki_mlist, nm_list, nmsg) { 543 if (msg->nm_predicate(msg)) { 544 TAILQ_REMOVE(&kqinfo->ki_mlist, msg, nm_list); 545 lwkt_replymsg(&msg->base.lmsg, 546 msg->base.lmsg.ms_error); 547 } 548 } 549 if (TAILQ_EMPTY(&ssb->ssb_kq.ki_mlist)) 550 atomic_clear_int(&ssb->ssb_flags, SSB_MEVENT); 551 lwkt_relpooltoken(so); 552 } 553 } 554 555 /* 556 * Socket buffer (struct signalsockbuf) utility routines. 557 * 558 * Each socket contains two socket buffers: one for sending data and 559 * one for receiving data. Each buffer contains a queue of mbufs, 560 * information about the number of mbufs and amount of data in the 561 * queue, and other fields allowing kevent()/select()/poll() statements 562 * and notification on data availability to be implemented. 563 * 564 * Data stored in a socket buffer is maintained as a list of records. 565 * Each record is a list of mbufs chained together with the m_next 566 * field. Records are chained together with the m_nextpkt field. The upper 567 * level routine soreceive() expects the following conventions to be 568 * observed when placing information in the receive buffer: 569 * 570 * 1. If the protocol requires each message be preceded by the sender's 571 * name, then a record containing that name must be present before 572 * any associated data (mbuf's must be of type MT_SONAME). 573 * 2. If the protocol supports the exchange of ``access rights'' (really 574 * just additional data associated with the message), and there are 575 * ``rights'' to be received, then a record containing this data 576 * should be present (mbuf's must be of type MT_RIGHTS). 577 * 3. If a name or rights record exists, then it must be followed by 578 * a data record, perhaps of zero length. 579 * 580 * Before using a new socket structure it is first necessary to reserve 581 * buffer space to the socket, by calling sbreserve(). This should commit 582 * some of the available buffer space in the system buffer pool for the 583 * socket (currently, it does nothing but enforce limits). The space 584 * should be released by calling ssb_release() when the socket is destroyed. 585 */ 586 int 587 soreserve(struct socket *so, u_long sndcc, u_long rcvcc, struct rlimit *rl) 588 { 589 if (so->so_snd.ssb_lowat == 0) 590 atomic_set_int(&so->so_snd.ssb_flags, SSB_AUTOLOWAT); 591 if (ssb_reserve(&so->so_snd, sndcc, so, rl) == 0) 592 goto bad; 593 if (ssb_reserve(&so->so_rcv, rcvcc, so, rl) == 0) 594 goto bad2; 595 if (so->so_rcv.ssb_lowat == 0) 596 so->so_rcv.ssb_lowat = 1; 597 if (so->so_snd.ssb_lowat == 0) 598 so->so_snd.ssb_lowat = MCLBYTES; 599 if (so->so_snd.ssb_lowat > so->so_snd.ssb_hiwat) 600 so->so_snd.ssb_lowat = so->so_snd.ssb_hiwat; 601 return (0); 602 bad2: 603 ssb_release(&so->so_snd, so); 604 bad: 605 return (ENOBUFS); 606 } 607 608 static int 609 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 610 { 611 int error = 0; 612 u_long old_sb_max = sb_max; 613 614 error = SYSCTL_OUT(req, arg1, sizeof(int)); 615 if (error || !req->newptr) 616 return (error); 617 error = SYSCTL_IN(req, arg1, sizeof(int)); 618 if (error) 619 return (error); 620 if (sb_max < MSIZE + MCLBYTES) { 621 sb_max = old_sb_max; 622 return (EINVAL); 623 } 624 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES); 625 return (0); 626 } 627 628 /* 629 * Allot mbufs to a signalsockbuf. 630 * 631 * Attempt to scale mbmax so that mbcnt doesn't become limiting 632 * if buffering efficiency is near the normal case. 633 * 634 * sb_max only applies to user-sockets (where rl != NULL). It does 635 * not apply to kernel sockets or kernel-controlled sockets. Note 636 * that NFS overrides the sockbuf limits created when nfsd creates 637 * a socket. 638 */ 639 int 640 ssb_reserve(struct signalsockbuf *ssb, u_long cc, struct socket *so, 641 struct rlimit *rl) 642 { 643 /* 644 * rl will only be NULL when we're in an interrupt (eg, in tcp_input) 645 * or when called from netgraph (ie, ngd_attach) 646 */ 647 if (rl && cc > sb_max_adj) 648 cc = sb_max_adj; 649 if (!chgsbsize(so->so_cred->cr_uidinfo, &ssb->ssb_hiwat, cc, 650 rl ? rl->rlim_cur : RLIM_INFINITY)) { 651 return (0); 652 } 653 if (rl) 654 ssb->ssb_mbmax = min(cc * sb_efficiency, sb_max); 655 else 656 ssb->ssb_mbmax = cc * sb_efficiency; 657 658 /* 659 * AUTOLOWAT is set on send buffers and prevents large writes 660 * from generating a huge number of context switches. 661 */ 662 if (ssb->ssb_flags & SSB_AUTOLOWAT) { 663 ssb->ssb_lowat = ssb->ssb_hiwat / 2; 664 if (ssb->ssb_lowat < MCLBYTES) 665 ssb->ssb_lowat = MCLBYTES; 666 } 667 if (ssb->ssb_lowat > ssb->ssb_hiwat) 668 ssb->ssb_lowat = ssb->ssb_hiwat; 669 return (1); 670 } 671 672 /* 673 * Free mbufs held by a socket, and reserved mbuf space. 674 */ 675 void 676 ssb_release(struct signalsockbuf *ssb, struct socket *so) 677 { 678 sbflush(&ssb->sb); 679 (void)chgsbsize(so->so_cred->cr_uidinfo, &ssb->ssb_hiwat, 0, 680 RLIM_INFINITY); 681 ssb->ssb_mbmax = 0; 682 } 683 684 /* 685 * Some routines that return EOPNOTSUPP for entry points that are not 686 * supported by a protocol. Fill in as needed. 687 */ 688 void 689 pr_generic_notsupp(netmsg_t msg) 690 { 691 lwkt_replymsg(&msg->lmsg, EOPNOTSUPP); 692 } 693 694 int 695 pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio, 696 struct mbuf *top, struct mbuf *control, int flags, 697 struct thread *td) 698 { 699 if (top) 700 m_freem(top); 701 if (control) 702 m_freem(control); 703 return (EOPNOTSUPP); 704 } 705 706 int 707 pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr, 708 struct uio *uio, struct sockbuf *sio, 709 struct mbuf **controlp, int *flagsp) 710 { 711 return (EOPNOTSUPP); 712 } 713 714 /* 715 * This isn't really a ``null'' operation, but it's the default one 716 * and doesn't do anything destructive. 717 */ 718 void 719 pru_sense_null(netmsg_t msg) 720 { 721 msg->sense.nm_stat->st_blksize = msg->base.nm_so->so_snd.ssb_hiwat; 722 lwkt_replymsg(&msg->lmsg, 0); 723 } 724 725 /* 726 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. Callers 727 * of this routine assume that it always succeeds, so we have to use a 728 * blockable allocation even though we might be called from a critical thread. 729 */ 730 struct sockaddr * 731 dup_sockaddr(const struct sockaddr *sa) 732 { 733 struct sockaddr *sa2; 734 735 sa2 = kmalloc(sa->sa_len, M_SONAME, M_INTWAIT); 736 bcopy(sa, sa2, sa->sa_len); 737 return (sa2); 738 } 739 740 /* 741 * Create an external-format (``xsocket'') structure using the information 742 * in the kernel-format socket structure pointed to by so. This is done 743 * to reduce the spew of irrelevant information over this interface, 744 * to isolate user code from changes in the kernel structure, and 745 * potentially to provide information-hiding if we decide that 746 * some of this information should be hidden from users. 747 */ 748 void 749 sotoxsocket(struct socket *so, struct xsocket *xso) 750 { 751 xso->xso_len = sizeof *xso; 752 xso->xso_so = so; 753 xso->so_type = so->so_type; 754 xso->so_options = so->so_options; 755 xso->so_linger = so->so_linger; 756 xso->so_state = so->so_state; 757 xso->so_pcb = so->so_pcb; 758 xso->xso_protocol = so->so_proto->pr_protocol; 759 xso->xso_family = so->so_proto->pr_domain->dom_family; 760 xso->so_qlen = so->so_qlen; 761 xso->so_incqlen = so->so_incqlen; 762 xso->so_qlimit = so->so_qlimit; 763 xso->so_timeo = so->so_timeo; 764 xso->so_error = so->so_error; 765 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 766 xso->so_oobmark = so->so_oobmark; 767 ssbtoxsockbuf(&so->so_snd, &xso->so_snd); 768 ssbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 769 xso->so_uid = so->so_cred->cr_uid; 770 } 771 772 /* 773 * Here is the definition of some of the basic objects in the kern.ipc 774 * branch of the MIB. 775 */ 776 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 777 778 /* 779 * This takes the place of kern.maxsockbuf, which moved to kern.ipc. 780 * 781 * NOTE! sb_max only applies to user-created socket buffers. 782 */ 783 static int dummy; 784 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 785 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_INT|CTLFLAG_RW, 786 &sb_max, 0, sysctl_handle_sb_max, "I", "Maximum socket buffer size"); 787 SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD, 788 &maxsockets, 0, "Maximum number of sockets available"); 789 SYSCTL_INT(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 790 &sb_efficiency, 0, 791 "Socket buffer limit scaler"); 792 793 /* 794 * Initialize maxsockets 795 */ 796 static void 797 init_maxsockets(void *ignored) 798 { 799 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 800 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 801 } 802 SYSINIT(param, SI_BOOT1_TUNABLES, SI_ORDER_ANY, 803 init_maxsockets, NULL); 804 805